Java 如果按钮符合某些期望，如何修改它的文本

如何有条件地对按钮执行操作:

1. 定义按钮的操作处理程序.
2. 在操作处理程序中，测试以查看是否满足所需的条件.
3. 如果测试通过，请执行所需的操作.

Short example个

final Button button = new Button(word);
button.setOnAction(e -> {
    if (isRequiredWord(word)) {
        button.setText(MATCHED_VALUE);
    }
});

Sample application

显示带有文字的按钮网格.如果用户单击一个单词以字母"a"开头、不区分大小写的按钮，则按钮文本将从显示的单词更改为"X".

import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.GridPane;
import javafx.stage.Stage;

public class MatchingGameApp extends Application {
    private static final String MATCHED_VALUE = "X";
    private static final String[][] animalBoard = {
            { "cat", "ape" },
            { "aardvark", "dog" }
    };

    /**
     * Add actionable buttons to a grid.
     *
     * @param board A 2D array of words.
     * @param grid a GridPane to which buttons for each word will be added.
     */
    private void addButtons(String[][] board, GridPane grid) {
        for (int i = 0; i < board.length; i++) {
            for (int j = 0; j < board[i].length; j++) {
                final String word = board[i][j];

                final Button button = new Button(word);
                button.setPrefWidth(80);
                button.setOnAction(e -> {
                    if (isRequiredWord(word)) {
                        button.setText(MATCHED_VALUE);
                    }
                });

                grid.add(button, i, j);
            }
        }
    }

    /**
     * A required word is any word starting with a letter "a" in any case.
     */
    public boolean isRequiredWord(String word) {
        return word != null && !word.isEmpty() &&
                word
                        .substring(0, 1)
                        .toLowerCase()
                        .startsWith("a");
    }

    @Override
    public void start(Stage stage) {
        GridPane layout = new GridPane(10, 10);
        layout.setPadding(new Insets(10));

        addButtons(animalBoard, layout);

        stage.setScene(new Scene(layout));
        stage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}